Funny, I love Ruby and it's my primary language of choice, but I'm a heretic, using braces whenever I can:

    # events per day
    ndbh.fetch('select ts from tbl').all.map { |row| 
        row[:ts]
    }.map { |t|
        t.strftime('%Y-%m-%d')
    }.each { |day|
        days[day] += 1
    }

(yes this could be conciser)

This is generally frowned on, and I'm sure everyone who likes having this style

   foo
     .map {}
     .select {}
     .blah {}

will frown as well, but it's so much more visually appealing to me, coming from a C/perl background when I first encountered Ruby (many years ago).

Funny how important syntax is. So easy to look at code in another style/language and go THATS NOT RIGHT!!